A 25-year-old man paralyzed from the chest down can stand, bear weight for four minutes at a time and take stepping motions courtesy of epidural electrical stimulation in the lower spinal cord.
The breakthrough, delivered by a team of scientists at the University of Louisville, UCLA and the California Institute of Technology, revolves around "continual direct epidural electrical stimulation." These electrical signals mimic the signals the brain transmits to start movement.
Once the signal is given, the spinal cord's neural network along with input from the legs can start muscle and joint movements. The paraplegic man, Rob Summers, 25, was completely paralyzed from the chest down after a hit-and-run accident in 2006.
In the context of Summers case, researchers described the stimulation this way:
Epidural stimulation is the application of continuous electrical current, at varying frequencies and intensities to specific locations on the lumbosacral spinal cord corresponding to the dense neural bundles that largely control movement of the hips, knees, ankles and toes. The electrodes required for this stimulation were implanted at University of Louisville Hospital by Dr. Jonathan Hodes, chairman of the Department of Neurosurgery at the University of Louisville.
The findings were published in The Lancet, a British medical journal.
CBS News quoted Summers saying: "I stood - independently - stood. After not having moved anything for four years ... and I stood."